Floats set too low

[Guest]

What are the main symptoms of having the floats set toop lean, i know you will run out of fuel at wot, but can it effect idle?

Im only asking because my I went through the carbs and cleaned them, boiled the carb bodies, new jets, cleaned the needle jet holder, and the thing only runs with full choke,and it revs out like its lean, the second I shut the choke off it stalls, also if I open the throttle it stalls.

I made sure the air box was sealed. I installed new carb boot o-rings. Boots where good.

I did set the floats but now since I looked online it seems like I set them lean, I was setting them to the flat spot on the floats, closest to the needle valve.

[wymple]

I don't know about your carbs in particular, but on some carbs the idle circuitry is the 1st to come up short with low fuel bowl levels. There are many guys in this place who will most likely set this straight for you.

[Steve]

Sorry, but I just can't pass up this opportunity.

What are the main symptoms of having the floats set toop lean, i know you will run out of fuel at wot, but can it effect idle?

A proper float level setting will effect idle, but a wrong float level setting will affect idle.


Now, when you say you set the level "low", do you mean an actual "low" or did you see lower-than-specified numbers on the height gauge?

If you are working on the 550, specs call for 22.4mm +/- 1.0mm. If you set the floats to less than 21.4, the floats are actually HIGHER than specified, because you are measuring the distance from the TOP of travel to the carb body. Remember, the carbs are upside down when you do this measurement. If that's what you did, you are actually running RICH, not lean.

On the other hand, if you used numbers greater than 23.4mm, the floats are, indeed, too low, and you will be running lean.

It also matters where you do the measurement. You should measure from the BOTTOM of the step, not the top.

Will it affect the idle? Yes. It will also affect the needle circuit. Oh, it will also affect the main circuit. Setting proper float height is probably the most important thing you can to for your carbs, because EVERYTHING ELSE depends on having that proper amount of fuel.

.

[Agemax]

also make sure you remove the float bowl gasket before taking the measurement

[curtie94]

I adjusted the floats, some where lean and some where rich. But it still didn't seem to fix my issue.

I got it to start after it turned over for awhile, I have some throttle response but it is acting like a air leak, I open the throttle and about a second later the rpms sky rocket them slowly come back down.

I think maybe my air box lid isn't sealing, because I tried it withe lid off and it acted the same way. is there any way i can seal the lid quickly to rule it in or out?

It starts hard every time.

When I had the carbs out I bench synced them again just to be sure, I also made sure the idle circuit and all other carb circuits where clean and free.

I am not used to working on these cv carbs, everyother bike I have uses either vm or keihin.

[curtie94]

I ended up taking the filter out of the air box and stuffed a t-shirt in there, and it runs great like that. SO the that tells me the air box cover is not sealing.

What can I use to seal the air box?

[lemonshindig]

Sorry, but I just can't pass up this opportunity.


A proper float level setting will effect idle, but a wrong float level setting will affect idle.

.

You're wrong. Affect is a verb and effect is a noun (a result, usually). You can have an effect on idle, but you must affect idle.

http://grammar.yourdictionary.com/style-and-usage/affect-effect-grammar.html

[lemonshindig]

Airbox sealing:

http://members.dslextreme.com/users/cbsaunders/gs/airbox-sealing.pdf

[curtie94]

Are the air boxes a two piece?

Or is the lid the only thing that needs sealing on the 550s?

I checked out the pdf but I'm still a little confused.

I have to pull the head anyway to do a head gasket so I'm pull the airbox then.

[lemonshindig]

I'm not sure, my bikes are older than yours with bigger engines.

I sort of doubt that the lid is your problem. I'd seal it anyway, with some closed-cell foam tape, but I bet you've got a carb problem. It might be floats, dirty carbs, mixture screws set to lean, or vacuum leaks at your airbox boots.

[londonboards]

Just in case you were still not getting anywhere:

I had this problem:

It just died when you opened the throttle.

It transpired that as soon as the throttle was opened sufficiently to engage the main jets, there was complete fuel starvation. The problem was the needles in the main jets. I had assembled the needles in the throttle slides incorrectly with the spring in the wrong place:



This may not be your exact problem but I would suggest a revisit to the throttle slides and needles.

Also (and I will be shouted down about this) in my experience of these motors, you should be able to start them up and run them with no airbox and no exhaust pipe. For testing purposes, they will run up throughout the rev range in this condition but obviously not to their full potential. Looking for hairline cracks in the airbox won't provide the answer to why your bike won't spin up. That is my experience.

Viz my Road Runner sans header. Great way to check which pot is spitting at you:

Greetings